//package com.lmq.interfaces;// interfaces/SameFile.java
//// (c)2021 MindView LLC: see Copyright.txt
//// We make no guarantees that this code is fit for any purpose.
//// Visit http://OnJava8.com for more book information.
//// {NewFeature} Since JDK 17
//
//sealed class Shape {}
//final class Circle extends Shape {}
//final class Triangle extends Shape {}
